CAUSE

This issue occurs because the federation certificate is missing from the server that's running Microsoft Exchange 2010. This server is also known as the hybrid server. When you run the Get-FederationInformation cmdlet, the cmdlet tries to obtain federation info about the on-premises hybrid server.

The Test-FederationTrust cmdlet reveals this issue more accurately. For example, after you run the Test-FederationTrust cmdlet, the result resembles the following:

Restart the MSExchangeServicesAppPool application pool by using the Internet Information Services (IIS) 7 console. For more info about how to restart application pools in IIS 7, go to the following Microsoft website: